Effects of L-Lysine Pretreatment and Sterilization Process on the Quality of Canned Antarctic Krill

Abstract

This study aimed to study the effects of sterilization temperature and time on the quality of canned Antarctic krill pretreated with L-lysine (Lys) at the same sterilization intensity. Pretreatment with either water or the water-retaining agent sodium tripolyphosphate (STPP) served as control. Four combinations of sterilization temperature and time were established as follows: 115 ℃ for 60 min, 117 ℃ for 38 min, 119 ℃ for 24 min, and 121 ℃ for 15 min. After sterilization at 115 ℃ for 60 min, the Lys-treated group had lower hardness and chewiness and the lowest degree of lipid oxidation. Low-field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) analysis indicated the largest peak area of immobilized water and the highest signal intensity in the pseudo-color image. The microstructure analysis showed that the muscle tissue treated with Lys had a more regular and complete structure with uniformly distributed pores. The sensory evaluation results showed that Antarctic krill meat treated with Lys and sterilized at 115 ℃ for 60 min had better flavor and texture, and scored highest in acceptability. In conclusion, Lys could be a substitute for phosphate to improve the quality of canned Antarctic krill, and sterilization at 115 ℃ for 60 min was the optimal sterilization conditions to maintain the quality of canned Antarctic krill. Lys pretreatment combined with this sterilization process has good applicability in actual production.

Keywords

• canned antarctic krill (euphausia superba); l-lysine; sterilization; quality improvement